Inline Gearbox with Fast Change Gearing

ABSTRACT

An inline gearbox for a land vehicle that includes an engine having a clutch housing for the transmission of rotational force from the engine to one or more wheels for propelling the land vehicle, wherein the inline gearbox includes a gearbox housing having a front end, a side and a rear end, with the front end adapted to be joined to the clutch housing. There is an input shaft contained at least in part within the gearbox housing proximate to the front end of the gearbox housing, and a primary gear train that includes (a) a lay shaft; (b) a drive shaft; and (c) a plurality of selectively engaged meshed gear pairs respectively mounted on the lay shaft and the drive shaft for transmitting rotational force from the lay shaft to the drive shaft. The inline gearbox also includes an output shaft contained at least in part within the gearbox housing proximate to the rear end of the gearbox housing, with the output shaft rotationally coupled to the drive shaft. The inline gearbox features a fast-change gear assembly contained within the gearbox housing, where the fast-change gear assembly is positioned proximate the front end of the gearbox housing and interposed between the input shaft and the lay shaft, with the fast-change gear assembly comprising a first fast-change gear and a second fast-change gear meshing with the first fast-change gear, and with the first fast-change gear and the second fast-change gear each having an axis generally parallel to the axis of the input shaft. The first fast-change gear is rotationally coupled to the input shaft so as to rotate with the rotation of the input shaft, and translationally uncoupled to the input shaft to permit removal of the first fast-change gear from the gearbox housing; and the second fast-change gear is rotationally coupled to the lay shaft so as to rotate the lay shaft upon rotation of the second fast-change gear, and translationally uncoupled to the lay shaft to permit removal of the second fast-change gear from the gearbox housing.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.16/670,688, filed on Oct. 31, 2019, which claims the benefit of U.S.Provisional Application No. 62/754,667, filed Nov. 2, 2018, and is acontinuation-in-part application of U.S. patent application Ser. No.16/168,957 (now U.S. Pat. No. 11,193,574), filed Oct. 24, 2018, whichclaims the benefit of U.S. Provisional Application No. 62/577,423, filedOct. 26, 2017, U.S. Provisional Application No. 62/577,965, filed Oct.27, 2017, U.S. Provisional Application No. 62/616,601, filed Jan. 12,2018 and U.S. Provisional Application No. 62/735,966, filed Sep. 25,2018.

BACKGROUND OF THE INVENTION Field of the Invention

This invention relates to gearbox design.

Description of the Related Art

Gear systems are used in order to better match the torque, power androtational speed characteristics of a rotating power source with theneeds of the application. In the case of gearboxes used in connectionwith internal combustion engines for automotive applications, currentdesigns generally are limited to use in relatively narrow performancebands, and do not lend themselves well to use in a wide variety ofdifferent types of vehicles. For example, a gearbox suitable for a highperformance automobile intended for a paved racetrack may proveunsuitable if used in an off-road vehicle.

This drawback of current automotive gearbox design may be particularlyexperienced, for example, in the case of a base vehicle intended to bemarketed for different applications, such as for street, track,off-road, etc. Current options may disadvantageously require the gearboxmanufacturer to offer a number of gearbox/differential/transfer caseunits of different design, since a gearbox having appropriate powertransmission characteristics for one application may not be appropriatefor another desired application. Likewise, an automotive manufacturermay need to order and maintain a different gearbox for each of itsofferings intended for a different target performance market.

This drawback also presents itself in the case of vehicles which may bemodified or customized post-sale by automotive enthusiasts. For suchvehicles, a decision to change the performance characteristics of thevehicle might necessitate purchase and installation of a differentgearbox design, at substantial time and expense.

SUMMARY OF THE INVENTION

The present invention provides a gearbox design that can be used for awide variety of applications that heretofore could require differentgearboxes, particularly for land vehicles utilizing an engine, such asan internal combustion engine, for propulsion.

The gearbox of the present invention is suited for use in vehicles whichmay be modified or customized post-sale, such as those disclosed in U.S.Patent Publication No. 2015/0210319 A1.

In a first aspect, the present invention is directed to an inlinegearbox for a land vehicle that includes an engine having a clutchhousing for the transmission of rotational force from the engine to oneor more wheels for propelling the land vehicle, wherein the inlinegearbox comprises a gearbox housing having a front end, a side and arear end, with the front end adapted to be joined to the clutch housing.There is provided an input shaft having an axis and contained at leastin part within the gearbox housing proximate to the front end of thegearbox housing, with the input shaft adapted to receive rotationalforce from the engine through the clutch housing, and a primary geartrain contained within the gearbox housing comprising (a) a lay shafthaving an axis generally parallel to the axis of the input shaft androtationally coupled to the input shaft to receive rotational force fromthe input shaft, the axes of the input shaft and the lay shaft beingspaced-apart to define a forward plane; (b) a drive shaft; and (c) aplurality of selectively engaged meshed gear pairs respectively mountedon the lay shaft and the drive shaft for transmitting rotational forcefrom the lay shaft to the drive shaft. The inline gearbox also includesan output shaft having an axis generally parallel to the axis of the layshaft and contained at least in part within the gearbox housingproximate to the rear end of the gearbox housing, with the output shaftrotationally coupled to the drive shaft to receive rotational force fromthe drive shaft and for transmitting rotational force to the one or morewheels, the axes of the output shaft and the lay shaft being space-apartto define a rear plane.

In this first aspect of the present invention, the inline gearboxfeatures a fast-change gear assembly contained within the gearboxhousing, the fast-change gear assembly being positioned proximate thefront end of the gearbox housing and interposed between the input shaftand the lay shaft, with the fast-change gear assembly comprising a firstfast-change gear and a second fast-change gear meshing with the firstfast-change gear, and with the first fast-change gear and the secondfast-change gear each having an axis generally parallel to the axis ofthe input shaft. The first fast-change gear is rotationally coupled tothe input shaft so as to rotate with the rotation of the input shaft,and translationally uncoupled to the input shaft to permit removal ofthe first fast-change gear from the gearbox housing; and the secondfast-change gear is rotationally coupled to the lay shaft so as torotate the lay shaft upon rotation of the second fast-change gear, andtranslationally uncoupled to the lay shaft to permit removal of thesecond fast-change gear from the gearbox housing.

In a second aspect of this invention, the inline gearbox utilizes thegearbox housing, input shaft, primary gear train and output shaftarrangement of the first aspect of the invention, but with a differentfast-change gear arrangement. More specifically, the second aspect ofthe invention features a fast-change gear assembly positioned proximatethe front end of the gearbox housing and interposed between the inputshaft and the lay shaft, and located to one side of a forward planedefined by the axes of the input shaft and the lay shaft. Thefast-change gear assembly comprises a first fast-change gear and asecond fast-change gear meshing with the first fast-change gear, thefirst fast-change gear and the second fast-change gear having respectivefirst and second fast-change gear axes that are both approximatelyperpendicularly oriented to a direction on the forward planeapproximately perpendicular to the axis of the input shaft. The firstfast-change gear is rotationally coupled to the input shaft so as torotate with the rotation of the input shaft and is removable. The secondfast-change gear is rotationally coupled to the lay shaft so as torotate the lay shaft upon rotation of the second fast-change gear, andis removable.

In a third aspect, the present invention is directed to an inlinegearbox for a land vehicle that includes an engine having a clutchhousing for the transmission of rotational force from the engine to oneor more wheels for propelling the land vehicle, wherein the inlinegearbox comprises a gearbox housing having a front end, a side and arear end, with the front end adapted to be joined to the clutch housing.There is provided an input shaft having an axis and contained at leastin part within the gearbox housing proximate to the front end of thegearbox housing, with the input shaft adapted to receive rotationalforce from the engine through the clutch housing, and a primary geartrain contained within the gearbox housing comprising (a) a lay shafthaving an axis generally parallel to the axis of the input shaft, theaxes of the input shaft and the lay shaft being spaced-apart to define aforward plane; (b) a drive shaft rotationally coupled to the input shaftto receive rotational force from the input shaft; and (c) a plurality ofselectively engaged meshed gear pairs respectively mounted on the layshaft and the drive shaft for transmitting rotational force from thedrive shaft to the lay shaft. The inline gearbox also includes an outputshaft having an axis generally parallel to the axis of the lay shaft andcontained at least in part within the gearbox housing proximate to therear end of the gearbox housing, with the output shaft rotationallycoupled to the lay shaft to receive rotational force from the lay shaftand for transmitting rotational force to the one or more wheels, theaxes of the output shaft and the lay shaft being space-apart to define arear plane.

In this third aspect of the subject invention, the inline gearboxfeatures a fast-change gear assembly contained within the gearboxhousing, positioned proximate the rear end of the gearbox housing andinterposed between the output shaft and the lay shaft. The fast-changegear assembly comprises a first fast-change gear and a secondfast-change gear meshing with the first fast-change gear, the firstfast-change gear and the second fast-change gear each having an axisgenerally parallel to the axis of the output shaft. The firstfast-change gear is rotationally coupled to the lay shaft so as torotate with the rotation of the lay shaft, and translationally uncoupledto the lay shaft to permit removal of the first fast-change gear fromthe gearbox housing. The second fast-change gear is rotationally coupledto the output shaft so as to rotate the output shaft upon rotation ofthe second fast-change gear, and translationally uncoupled to the outputshaft to permit removal of the second fast-change gear from the gearboxhousing.

In a fourth aspect of this invention, the inline gearbox utilizes thegearbox housing, input shaft, primary gear train and output shaftarrangement of the third aspect of the invention, but with a differentfast-change gear arrangement. More specifically, the fourth aspect ofthe invention features a fast-change gear assembly positioned proximatethe rear end of the gearbox housing and interposed between the outputshaft and the lay shaft, and located to one side of the rear planedefined by the axes of the output shaft and the lay shaft. Thefast-change gear assembly comprises a first fast-change gear and asecond fast-change gear meshing with the first fast-change gear, thefirst fast-change gear and the second fast-change gear having respectivefirst and second fast-change gear axes that are both approximatelyperpendicularly oriented to a direction on the rear plane approximatelyperpendicular to the axis of the output shaft. The first fast-changegear is rotationally coupled to the lay shaft so as to rotate with therotation of the lay shaft and is removable. The second fast-change gearis rotationally coupled to the output shaft so as to rotate the outputshaft upon rotation of the second fast-change gear, and is removable.

These and other aspects of the present invention are described in thedrawings annexed hereto, and in the description of the preferredembodiments and claims set forth below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic perspective view depicting certain principalcomponents of the present invention, as well as certain geometricalaspects of the present invention, utilizing the first embodiment of thepresent invention for illustrative purposes.

FIG. 1B is a schematic perspective view of the first embodiment of thepresent invention, identifying particular gear and shaft components alsopresent in FIG. 1A.

FIG. 2 is a schematic perspective view of the second embodiment of thepresent invention.

FIG. 3 is a schematic perspective view of the third embodiment of thepresent invention.

FIG. 4A is a schematic perspective view of the fourth embodiment of thepresent invention

FIG. 4B is a schematic top view of the fourth embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Overall GearboxDescription

Referring to FIG. 1A, there is shown an inline gearbox 1 that includes aprimary gear train 2. Through the intermediary of a clutch assembly orclutch 3, an engine rotates an input shaft 6 of gearbox 1. Input shaft 6in turn rotationally energizes primary gear train 2 (described furtherbelow), which in turn rotates output shaft 13.

In a typical application, the input shaft 6 of inline gearbox 1 iscoupled to a reciprocating piston internal combustion engine and isemployed to propel a motor vehicle. In such an application, the outputshaft 13 will rotate one or more wheels, usually by way of rotating adrive shaft linked to differential gearing housed distally separate frominline gearbox 1 (such differential gearing and its housing oftenreferred to simply as a “differential”), which distributes the receivedrotational force to wheels located on opposite sides of the vehicle.Exemplary engines for such an application include spark-ignition liquidfueled (e.g., gasoline) V-8 engines.

The term “primary gear train” in this disclosure denotes the gearingassembly through which the torque and rotation imparted by the engineare transmitted, and includes means for selectively activating one ofplural gear pairs of varying diameters during engine operation in orderto change the angular speed/torque characteristics that are output fromthe primary gear train, in order to match the application requirementsas they vary during driver use, such as, in the case of a motor vehiclejourney, initial movement from standing, acceleration/passing, low speedand high speed movement at uniform speed, and the like. The primary geartrain does not include differential gearing of the type referencedabove, which is typically utilized to provide or respond to differentwheel rotational speeds encountered in vehicle turns, or differentlevels of tractions between wheels.

Throughout this disclosure, like designations in the embodiments denotethe same components. The overall gearbox description of inline gearbox 1and its gearbox components described herein with reference to FIGS. 1Aand 1B is applicable to all four embodiments of the present inventiondescribed below (and illustrated in FIGS. 1A-4B).

The term “inline gearbox” in this disclosure denotes a class ofgearboxes in which the axes of the principal rotating shafts in theprimary gear train, in the present disclosure the axes of drive shaft110 and lay shaft 120 of primary gear train 2, are approximatelyparallel to the axis of the input shaft 6 from the engine and clutch 3(and correspondingly parallel to each other). In turn, input shaft 6would be approximately parallel to the centerline of the enginecrankshaft.

The axial centerline (axis) of input shaft 6 of gearbox 1 in FIG. 1A isindicated as 890. The orientation of gearbox 1 as depicted in FIG. 1A(and in FIGS. 1B-4A as well) is arbitrarily denominated the uprightorientation, and arrow 910 points in an upward or vertical direction. Inthe figures, arrow 920 is longitudinally oriented and is arbitrarilydeemed to point in the forward direction; thus in FIG. 1A (and in theother figures as well), the rotational force from the engine crankshaftavailable at the rear or rearward end of the engine would be coupled tothe forward end of the clutch 3 (the widest end of clutch 3 in thefigures).

As indicated above, primary gear train 2 comprises a drive shaft 110 anda lay shaft 120. As shown in FIG. 1A, the axes of input shaft 6 and layshaft 120 are spaced-apart and parallel with each other to define alongitudinally oriented forward plane 821, and the axes of output shaft13 and lay shaft 120 are spaced-apart and parallel with each other todefine a longitudinally oriented rear plane 822. While planes 821 and822 are depicted only in FIG. 1A for purposes of clarity, they arereferred to at times in regard to embodiments of the present inventiondepicted in the other figures (other than FIG. 1A). Accordingly, planes821 and 822 should be considered present in those other figures to thesame extent as is shown in FIG. 1A. In the embodiment shown in FIG. 1A,planes 821 and 822 are coplanar (but they need not be), andvertically-oriented (but they need not be). Arrows 910 and 920 in FIG.1A lie in a plane that is coplanar with forward plane 821. In thisdisclosure, a component is deemed to be positioned on the “side” or toone “side” of gearbox 1 or gearbox housing 18 if it is positioned forthe most part to one side of plane 821 or plane 822, as specified.

Gearbox Components

Primary gear train 2 of gearbox 1 is contained within a gearbox housing18 having a forward or front end 181 proximate to clutch 3 and arearward or rear end 182 distal from clutch 3. Housing 18, front end 181and rear end 182 are shown in outline (dashed lines) in FIGS. 1A and 3,and are omitted from the balance of the figures for purposes ofsimplifying the drawings. Nonetheless, gearbox housing 18, front end 181and rear end 182 should be considered part of every embodiment andfigure in this disclosure as if expressly illustrated therein.

The operative portions of clutch 3 are contained within a clutch housing33, which is shown in outline (dashed lines) in FIGS. 1A and 3, andwhich is omitted from the balance of the figures for purposes ofsimplifying the drawings. Nonetheless, clutch housing 33 should beconsidered part of every embodiment and figure in this disclosure as ifexpressly illustrated therein. In this disclosure, it is assumed thatthe forward or front end of clutch housing 33 is secured to the rearwardor rear end of the engine utilizing for example bolts.

Typically gearbox housing 18 is also secured to clutch housing 33 withbolts, and the two assemblies can be separated for maintenance, serviceand the like. To facilitate ease of separation, the forward end of inputshaft 6 extending forward of front end 181 can have longitudinal splinesformed parallel to the axis of input shaft 6 which mate with a splinedaperture at the rear of clutch 3. Thus clutch 3 and input shaft 6 arerotationally coupled—rotation of clutch 3 will rotate input shaft 6;while clutch 3 and input shaft 6 are translationally uncoupled—gearbox 1can be separated from clutch 3 by unbolting gearbox 1 from clutch 3, anddisplacing gearbox 3 in the rearward direction.

The input shaft 6 of gearbox 1 passes into gearbox housing 18 at frontend 181 to rotate primary gear train 2, and primary gear train 2 rotatesoutput shaft 13, which passes out of gearbox housing 18 at rear end 182.Primary gear train 2 of gearbox 1 comprises five meshing gear pairs ondrive shaft 110 and lay shaft 120, which correspond to the forward gearsof a motor vehicle in which gearbox 1 is utilized. These five meshinggear pairs are 1st gear pair 10, 2nd gear pair 20, 3rd gear pair 30, 4thgear pair 40 and 5th gear pair 50, shown in FIG. 1B and elsewhere.

Gear pairs 10-50 are selectively engaged for transmitting torque to androtating output shaft 13. As an example of means for so selectivelyengaging gear pairs 10-50, gears 121, 122, 123, 124, and 125 of gearpairs 10, 20, 30, 40 and 50 respectively, shown in FIGS. 1A-1B and alsoin FIGS. 2-4B, are considered to be axially and angularly secured atfixed positions along lay shaft 120; thus gears 121, 122, 123, 124 and125 cannot be shifted laterally (in the longitudinal direction, parallelto axis 890) along lay shaft 120, and gears 121, 122, 123, 124 and 125must rotate with the rotation of lay shaft 120. In comparison, gears111, 112, 113, 114 and 115 of gear pairs 10, 20, 30, 40 and 50 areconsidered to be axially secured at fixed positions along the length ofdrive shaft 110 (and thus cannot be shifted laterally along the shaft),but are mounted to freewheel on drive shaft 110 (i.e., rotationallyuncoupled to drive shaft 110).

In this example of means for selectively engaging gear pairs 10-50,there is additionally considered to be gear shift clutches (omitted forpurposes of clarity) proximate to each of gears 111, 112, 113, 114 and115. Each gear shift clutch includes an annular ring mounted on driveshaft 110 that maintains angular correspondence and rotates with driveshaft 110 (for example by means of splines), but which is free to beshifted laterally (in the longitudinal direction, parallel to axis 890)along drive shaft 110. Each gear shift clutch further includes a forkthat shifts the annular ring laterally on drive shaft 110, either uponmanual actuation by a driver or automatic actuation by an automaticshifting mechanism. When a gear shift clutch is shifted laterally ondrive shaft 110, it engages/disengages one or more of gears 111, 112,113, 114 and 115. When such a gear is engaged, the gear is rotationallycoupled to drive shaft 110, thereby to change the ratio of therotational speed of the input shaft 6 and the output shaft 13 inaccordance with the gear diameters of the engaged gear pair. (In thefigures of this disclosure, the diameters of the gear pairs arerepresentative only and are not intended to be indicative of specificgearing ratios). Further specifics as to the structure and operation ofgear shift clutches can be found at 919134-39 of U.S. Provisional PatentApplication Nos. 62/577,423, filed Oct. 26, 2017 and 62/577,965, filedOct. 27, 2017; the contents of those paragraphs (and the figures towhich those paragraphs refer, including FIGS. 3A-3E and 2A) are herebyincorporated by reference as if fully set forth herein. Those furtherspecifics also can be found at ¶¶ 35-40 of U.S. patent application Ser.No. 16/168,957, filed Oct. 24, 2018 and published May 2, 2019 as U.S.Patent Publication No. US 2019/0128381 A1; the contents of thoseparagraphs (and the figures to which those paragraphs refer, includingFIGS. 3A-3E and 2A) likewise are hereby incorporated by reference as iffully set forth herein.

Although five forward gears are shown, the teachings of this inventionare not dependent on the number of forward gears contained within inlinegearbox 1, and can be used in a gearbox containing other numbers offorward gears. Further, there can also be provided a reverse gearassembly, in order to reverse the direction of rotation (not shown).

Embodiment 1

The first embodiment of the present invention, which is shown in FIGS.1A and 1B, features a fast-change (“FC”) gear assembly 71 containedwithin gearbox housing 18, positioned proximate the front end 181 ofgearbox housing 18, interposed between input shaft 6 and lay shaft 120,and mounted on those shafts. Referring to FIG. 1B, input shaft 6transfers the engine torque to FC gear assembly 71, and then to layshaft 120 of primary gear train 2. Lay shaft 120 in turn rotates driveshaft 110 of gear train 2 via selective engagement of one of gear pairs10-50, as discussed above. Drive shaft 110 rotates output shaft 13 torotate the wheels. In the first embodiment shown in FIGS. 1A and 1B,output shaft 13 is the rear portion of drive shaft 110.

FC gear assembly 71 in the first embodiment comprises a first FC gear713 mounted on the rearward end of input shaft 6 (i.e., the portion ofinput shaft 6 furthest from the orientation designated by the head ofarrow 920), and a second FC gear 714 mounted on the forward end of layshaft 120 (i.e., the portion of input shaft 6 closest to the orientationdesignated by the head of arrow 920). First FC gear 713 meshes withsecond FC gear 714. First and second FC gears 713 and 714 can be spur orhelical in design, in accordance with preference subject to other designconstraints. The axes of first and second FC gears 713 and 714 each arelongitudinally oriented and lie in forward plane 821. The axis of firstFC gear 713 is co-linear with the axis (axis 890) of input shaft 6, andthe axis of second FC gear 714 is co-linear with the axis of lay shaft110.

First FC gear 713 is rotationally coupled to input shaft 6, such as bymeans of interior splines formed in first FC gear 713 which mate withexterior splines formed on the rearward end of input shaft 6; thesesplines are longitudinally oriented parallel with the axes of first FCgear 713 and input shaft 6. Likewise, second FC gear 714 is rotationallycoupled to lay shaft 120, such by means of interior splines formed insecond FC gear 714 which mate with exterior splines formed on theforward end of lay shaft 120; these splines are longitudinally orientedparallel with the axes of second FC gear 714 and lay shaft 120. Thusupon rotation of input shaft 6, first FC gear 713 will rotate, whichwill rotate second FC gear 714 and lay shaft 120. The rotational speedat which second FC gear 714 rotates will be the same as the speed atwhich first FC gear 713 rotates only in the case where they have thesame diameter. In the case where they are of different diameters, theirrotational speed will differ in direct proportion to the ratio of theirdiameters.

First FC gear 713 preferably is translationally uncoupled to input shaft6 to permit its removal. Thus first FC gear 713 is not permanentlyfastened to input shaft 6, but rather is preferably able to belongitudinally moved in a direction parallel to the axis (axis 890) ofinput shaft 6, such as by being slid along longitudinal splines of inputshaft 6, for removal and replacement. Likewise, second FC gear 74preferably is translationally uncoupled and not permanently fastened tolay shaft 120, but rather is preferably able to be longitudinally movedin a direction parallel to the axis of lay shaft 120, such as by beingslid along longitudinal splines of lay shaft 120, for removal andreplacement.

First and second FC gears 713 and 714 in the first embodiment can beaccessed, removed and changed in a variety of ways without the need todisassemble primary gear train 2, in accordance with the specificdesign. First and second FC gears 713 and 714 are accessible for exampleby separating gearbox housing 18 from clutch housing 33, without theneed to disassemble primary gear train 2. Alternatively, as shown inFIG. 1A, an access port 51 having a removable cover 52 can be providedat a suitable location on the side of gearbox housing 18 proximate tofront end 181 and to first and second FC gears 713 and 714, whichobviates the need for separating gearbox housing 18 from clutch housing33 in order to gain access to first and second FC gears 713 and 714.Access port 51 can also be positioned on the bottom of gearbox housing18, or on the top of gearbox housing 18, or at any other location aboutthe perimeter of gearbox housing 18 from which first and second FC gears713 and 714 are reasonably accessible. Access port 51 renders first andsecond FC gears 713 and 714 accessible for removal and replacementwithout the need for separating gearbox housing 18 from clutch housing33.

As a particular example of the benefits of the first embodiment of thesubject invention, a different rotational speed/torque relationship maybe desired when using inline gearbox 1 for a race track applicationinstead of an off-road application. In such a case, first and second FCgears 713 and 714 can be swapped out for gears of different diameters,which changes the rotational speed of output shaft 13 for a givenrotational speed of input shaft 6. In general, the gearbox inputshaft/output shaft speed ratio can be changed by utilizing first andsecond FC gears 713 and 714 of varying diameters without changing anygears of the primary gear train 2.

Embodiment 2

The second embodiment of the present invention, which is shown in FIG.2, features a FC gear assembly 72 positioned to one side of forwardvertical plane 821 of gearbox housing 18 proximate its front end 181,interposed between input shaft 6 and lay shaft 120, and mounted onshafts different from input shaft 6 and lay shaft 120. Referring to FIG.2, input shaft 6 transfers the engine torque to FC gear assembly 72, andthen to lay shaft 120 of primary gear train 2. Lay shaft 120 in turnrotates drive shaft 110 of gear train 2 via selective engagement of oneof gear pairs 10-50, as discussed above. Drive shaft 110 rotates outputshaft 13 to rotate the wheels. In the embodiment of FIG. 2, output shaft13 is the rear portion of drive shaft 110.

FC gear assembly 72 in the second embodiment comprises a first FC gear723 mounted on first FC gear shaft 725, and a second FC gear 724 mountedon second FC gear shaft 726. First FC gear 723 meshes with second FCgear 724. First and second FC gears 723 and 724 can be spur or helicalin design, in accordance with preference subject to other designconstraints. In a first variant of the second embodiment of the presentinvention, shown in FIG. 2, the axes of FC gear shafts 725 and 726 eachare orthogonal to longitudinally oriented forward plane 821 (plane 821being shown in FIG. 1A) in any two mutually perpendicular directions onforward plane 821, such that the axis of first FC gear shaft 725 isperpendicular to the axis of input shaft 6, and the axis of second FCgear shaft 726 is perpendicular to the axis of lay shaft 120.

In a second variant of the second embodiment of the present invention,the axes of first and second FC gear shafts 725 and 726 can betransversely oriented to the direction on forward plane 821 (plane 821being shown in FIG. 1A) that is approximately parallel to the axis ofinput shaft 6 and/or the axis of lay shaft 120 (which axes are parallelto each other, as described above). In this disclosure, the axes of FCgear shafts 725 and 726 are “transversely oriented” to forward plane 821as just described when they are oriented at a FC gear shaft angle αbetween zero and 90 degrees (90°>α>0°) relative to the axes of inputshaft 6/lay shaft 120, such as in the range of from 35 degrees to 75degrees (75°≥α≥35°), or more particularly in the range of from 45degrees to 60 degrees (60°≥α≥45°); for example, approximately 45 degrees(α≈45°) or approximately 60 degrees (α≈60°). Preferably, those axes offirst and second FC gear shafts 725 and 726 at the same time aremaintained at a right angle (or nearly so) to the direction on forwardplane 821 which is perpendicular to the axes of input shaft 6/lay shaft120. For any acute FC gear shaft angle, the FC gear shaft angle α, whenconsidered with the lengths of gear shafts 725 and 726, should besufficient to avoid first FC gear 723 and second FC gear 724 interferingwith either drive shaft 110 or lay shaft 120.

As shown in FIG. 2, a bevel gear 721 mounted on input shaft 6 mesheswith a bevel gear 729 mounted on first FC gear shaft 725, and a bevelgear 728 mounted on lay shaft 120 meshes with a bevel gear 727 mountedon second FC gear shaft 726. Bevel gears 721 and 729 can be spur orhelical in design, in accordance with preference subject to other designconstraints, and bevel gears 727 and 728 can be spur or helical indesign, in accordance with preference subject to other designconstraints. Upon rotation of input shaft 6, bevel gear 721 will rotate,which will rotate bevel gear 729 and first FC gear 723. The rotation offirst FC gear 723 will rotate second FC gear 724, which will rotatebevel gear 727. In turn, the rotation of bevel gear 727 will rotatebevel gear 728 and lay shaft 120. The rotational speed at which secondFC gear 724 rotates will be the same as the speed at which first FC gear723 rotates only in the case where they have the same diameter. In thecase where they are of different diameters, their rotational speed willdiffer in direct proportion to the ratio of their diameters.

First FC gear 723 preferably is not permanently fastened within gearbox1, but rather is secured in a manner to be removable from gearbox 1. Forexample, first FC gear 723 can be formed with interior splines that matewith exterior splines formed on first FC gear shaft 725; these splinespreferably are longitudinally oriented parallel with the axes of gear723 and first FC gear shaft 725. Thus first FC gear 723 is able to bemoved along the longitudinal splines of FC gear shaft 725 for removaland replacement. Alternatively, first FC gear 723 and first FC gearshaft 725 can be removable together as an integrated unit. As yetanother alternative, first FC gear 723, first FC gear shaft 725 andbevel gear 729 can be removable together as an integrated unit.

Likewise, second FC gear 724 preferably is not permanently fastenedwithin gearbox 1, but rather is secured in a manner to be removable fromgearbox 1, for example by being secured to be moveable along the axis ofsecond FC gear shaft 726, employing splines, or by being removable withsecond FC gear shaft 726, or by being removable with both second FC gearshaft 726 and bevel gear 727, in a manner comparable to that justdescribed.

First and second FC gears 723 and 724 in the second embodiment can beaccessed, removed and changed in a variety of ways without the need todisassemble primary gear train 2, in accordance with the specificdesign. First and second FC gears 723 and 724 can be located eitherwithin gearbox housing 18 or outside gearbox housing 18. If locatedwithin gearbox housing 18, first and second FC gears 723 and 724 areaccessible for example by separating gearbox housing 18 from clutchhousing 33, without the need to disassemble primary gear train 2.Alternatively, an access port having a removable cover can be providedon the side of gearbox housing 18 proximate to front end 181 and tofirst and second FC gears 723 and 724, which obviates the need forseparating gearbox housing 18 from clutch housing 33. If located outsidegearbox housing 18, first and second FC gears 723 and 724 can be locatedwithin an FC gear housing having a removable cover, which is positionedon the side of gearbox housing 18 proximate front end 181. The FC gearhousing design and associated components disclosed in U.S. patentapplication Ser. No. 16/168,957, filed Oct. 24, 2018 and published May2, 2019 as U.S. Patent Publication No. US 2019/0128381 A1, is pertinentin this regard. The contents of that patent application disclosing thedesign specifics of that FC gear housing and cover, and the FC geardesign and retention means therein, particularly the description foundat 91910041-0048 and shown in FIGS. 2A and 2B of that patentapplication, are incorporated by reference as if fully set forth herein.

Each of the access port/removable cover and separate housing justdescribed can also be positioned on the bottom of gearbox housing 18, oron the top of gearbox housing 18, or at any other location about theperimeter of gearbox housing 18 from which first and second FC gears 723and 724 are reasonably accessible, consistent with the orientation offorward plane 821.

As a particular example of the benefits of the second embodiment of thesubject invention, a different rotational speed/torque relationship maybe desired when using inline gearbox 1 for a race track applicationinstead of an off-road application. In such a case, first and second FCgears 723 and 724 can be swapped out for gears of different diameters,which changes the rotational speed of output shaft 13 for a givenrotational speed of input shaft 6. In general, the gearbox inputshaft/output shaft speed ratio can be changed by utilizing first andsecond FC gears 723 and 724 of varying diameters without changing any ofthe gears of primary gear train 2.

Embodiment 3

The third embodiment of the present invention, which is shown in FIG. 3,features a FC gear assembly 73, positioned proximate the rear end 182 ofgearbox housing 18, interposed between output shaft 13 and lay shaft120, and mounted on those shafts. Referring to FIG. 3, input shaft 6transfers the engine torque to rotate drive shaft 110 of primary geartrain 2. Drive shaft 110 in turn rotates lay shaft 120 of gear train 2via selective engagement of one of gear pairs 10-50, as discussed above.Lay shaft 120 rotates FC gear assembly 73, which rotates output shaft 13to rotate the wheels. In the third embodiment shown in FIG. 3, outputshaft 13 is not joined to drive shaft 110 (although it can beco-linear).

FC gear assembly 73 in the third embodiment comprises a first FC gear733 mounted on the rearward end of lay shaft 120, and a second FC gear734 mounted on the forward end of output shaft 13. First FC gear 733meshes with second FC gear 734. First and second FC gears 733 and 734can be spur or helical in design, in accordance with preference subjectto other design constraints. The axes of first and second FC gears 733and 734 each are longitudinally oriented, and lie in rear plane 822. Theaxis of first FC gear 733 is co-linear with the axis of lay shaft 120,and the axis of second FC gear 734 is co-linear with the axis of outputshaft 13. In the embodiment of FIG. 3, output shaft 13 is joined tosecond FC gear 734 and is rotated by that second FC gear 734.

First FC gear 733 is rotationally coupled to lay shaft 120, such as bymeans of interior splines formed in first FC gear 733 which mate withexterior splines formed on the rearward end of lay shaft 120; thesesplines are longitudinally oriented parallel with the axes of first FCgear 733 and lay shaft 120. Likewise, second FC gear 734 is rotationallycoupled to the forward end of output shaft 13, such as by means ofinterior splines formed in second FC gear 734 which mate with exteriorsplines formed on the forward end of output shaft 13; these splines arelongitudinally oriented parallel with the axes of second FC gear 734 andoutput shaft 13. Thus upon rotation of lay shaft 120, first FC gear 733will rotate, which will rotate second FC gear 734 and output shaft 13.The rotational speed at which second FC gear 734 rotates will be thesame as the speed at which first FC gear 733 rotates only in the casewhere they have the same diameter. In the case where they are ofdifferent diameters, their rotational speed will differ in directproportion to the ratio of their diameters.

First FC gear 733 preferably is translationally uncoupled to lay shaft120 to permit its removal. Thus first FC gear 733 is not permanentlyfastened to lay shaft 120, but rather is preferably able to belongitudinally moved in a direction parallel to the axis of lay shaft120, such as by being slid along longitudinal splines of lay shaft 120,for removal and replacement. Likewise, second FC gear 734 preferably istranslationally uncoupled and not permanently fastened to output shaft13, but rather preferably is removable, such as by being able to belongitudinally moved in a direction parallel to the axis of output shaft13, such as by being slid along longitudinal splines of output shaft 13,for removal and replacement, or by being removable with output shaft 13,in accordance with design preference.

First and second FC gears 733 and 734 in the third embodiment can beaccessed, removed and changed in a variety of ways without the need todisassemble primary gear train 2, in accordance with the specificdesign. First and second FC gears 733 and 734 can be located eitherwithin gearbox housing 18 or outside gearbox housing 18. If locatedwithin gearbox housing 18, first and second FC gears 733 and 734 can bemade accessible for example by providing an access port 53 having aremovable cover 54 proximate to the rear end 182 of gearbox housing 18and to first and second FC gears 733 and 734, such as on the side ofhousing 18 (shown in FIG. 3) or on the rear end 182 itself. Access port53 can also be positioned on the bottom of gearbox housing 18, or on thetop of gearbox housing 18, or at any other location about the perimeterof gearbox housing 18 from which first and second FC gears 733 and 734are reasonably accessible. If located outside gearbox housing 18, firstand second FC gears 733 and 734 can be located within a separate housinghaving a removable cover attached on the rear end 182 of gearbox housing18.

As a particular example of the benefits of the third embodiment of thesubject invention, a different rotational speed/torque relationship maybe desired when using inline gearbox 1 for a race track applicationinstead of an off-road application. In such a case, first and second FCgears 733 and 734 can be swapped out for gears of different diameters,which changes the rotational speed of output shaft 13 for a givenrotational speed of input shaft 6. In general, the gearbox inputshaft/output shaft speed ratio can be changed by utilizing first andsecond FC gears 733 and 734 of varying diameters without changing any ofthe gears of primary gear train 2.

Embodiment 4

The fourth embodiment of the present invention, which is shown in FIGS.4A and 4B, features a FC gear assembly 74 positioned to one side of rearvertical plane 822 of gearbox housing 18 proximate its rear end 182,interposed between lay shaft 120 and output shaft 13, and mounted onshafts different from output shaft 13 and lay shaft 120. Referring toFIGS. 4A and 4B, input shaft 6 transfers the engine torque to rotatedrive shaft 110 of primary gear train 2. Drive shaft 110 in turn rotateslay shaft 120 of gear train 2 via selective engagement of one of gearpairs 10-50, as discussed above. Lay shaft 120 rotates FC gear assembly74, which rotates output shaft 13 to rotate the wheels. In the fourthembodiment shown in FIGS. 4A-4B, output shaft 13 is not joined to driveshaft 110 (although it can be co-linear).

FC gear assembly 74 in the fourth embodiment comprises a first FC gear743 mounted on first FC gear shaft 745, and a second FC gear 744 mountedon second FC gear shaft 746 (visible in FIG. 4B). First FC gear 743meshes with second FC gear 744. First and second FC gears 743 and 744can be spur or helical in design, in accordance with preference subjectto other design constraints. In a first variant of the fourth embodimentof the present invention, shown in FIGS. 4A and 4B, the axes of FC gearshafts 745 and 746 each are orthogonal to longitudinally oriented rearplane 822 in any two mutually perpendicular directions on rear plane 822(plane 822 being shown in FIG. 1A), such that the axis of first FC gearshaft 745 is perpendicular to the axis of lay shaft 120, and the axis ofsecond FC gear shaft 746 is perpendicular to the axis of output shaft13.

In a second variant of the fourth embodiment of the present invention,the axes of first and second FC gear shafts 745 and 746 can betransversely oriented to the direction on rear plane 822 (plane 822being shown in FIG. 1A) that is approximately parallel to the axis oflay shaft 120 and/or the axis of output shaft 13 (which axes areparallel to each other, as described above). In this disclosure, theaxes of FC gear shafts 745 and 746 are “transversely oriented” to rearplane 822 as just described when they are oriented at a FC gear shaftangle β between zero and 90 degrees (90°>β>0°) relative to the axes ofoutput shaft 13/lay shaft 120, such as in the range of from 35 degreesto 75 degrees (75°≥β≥35°), or more particularly in the range of from 45degrees to 60 degrees (60°≥β≥45°); for example, approximately 45 degrees(β≈45°) or approximately 60 degrees (β≈60°. Preferably, those axes offirst and second FC gear shafts 745 and 746 at the same time aremaintained at a right angle (or nearly so) to the direction on rearplane 822 which is perpendicular to the axes of output shaft 13/layshaft 120.

Referring to FIGS. 4A and 4B, a bevel gear 741 mounted on the rear oflay shaft 120 meshes with a bevel gear 749 mounted on first FC gearshaft 745, and a bevel gear 748 mounted on output shaft 13 meshes with abevel gear 747 mounted on second FC gear shaft 746. Bevel gears 741 and749 can be spur or helical in design, in accordance with preferencesubject to other design constraints, and bevel gears 747 and 748 can bespur or helical in design, in accordance with preference and subject toother design constraints. Upon rotation of lay shaft 120, bevel gear 741will rotate, which will rotate bevel gear 749 and first FC gear 743. Therotation of first FC gear 743 will rotate second FC gear 744, which willrotate bevel gear 747. In turn, the rotation of bevel gear 747 willrotate bevel gear 748 and output shaft 13. The rotational speed at whichsecond FC gear 744 rotates will be the same as the speed at which firstFC gear 743 rotates only in the case where they have the same diameter.In the case where they are of different diameters, their rotationalspeed will differ in direct proportion to the ratio of their diameters.

First FC gear 743 preferably is not permanently fastened within gearbox1, but rather is secured in a manner to be removable from gearbox 1. Forexample, first FC gear 743 can be formed with interior splines that matewith exterior splines formed on first FC gear shaft 745; these splinespreferably are longitudinally oriented parallel with the axes of gear743 and shaft 745. Thus first FC gear 743 is able to be moved along thelongitudinal splines of first FC gear shaft 745 for removal andreplacement. Alternatively, first FC gear 743 and shaft 745 can beremovable together as an integrated unit. As yet another alternative,first FC gear 743, first FC gear shaft 745 and bevel gear 749 can beremovable together as an integrated unit.

Likewise, second FC gear 744 preferably is not permanently fastenedwithin gearbox 1, but rather is secured in a manner to be removable fromgearbox 1, for example by being secured to be moveable along the axis ofsecond FC gear shaft 746 employing splines, or by second gear 744 andsecond FC gear shaft 746 being removable together as an integrated unit,or with second gear 744, second FC gear shaft 746 and bevel gear 747being removable together as an integrated unit, in a manner comparableto that just described.

First and second FC gears 743 and 744 in the fourth embodiment can beaccessed, removed and changed in a variety of ways without the need todisassemble primary gear train 2, in accordance with the specificdesign. First and second FC gears 743 and 744 can be located eitherwithin gearbox housing 18 or outside gearbox housing 18. If locatedwithin gearbox housing 18, first and second FC gears 743 and 744 can bemade accessible for example by providing an access port having aremovable cover proximate to the rear end 182 of gearbox housing 18 andto first and second FC gears 743 and 744, such as on the side of housingor on the rear end 182 itself. If located outside gearbox housing 18,first and second FC gears 743 and 744 can be located within a housinghaving a removable cover attached on the side of gearbox housing 18proximate rear end 182. The FC gear housing design and associatedcomponents disclosed in U.S. patent application Ser. No. 16/168,957,filed Oct. 24, 2018 and published May 2, 2019 as U.S. Patent PublicationNo. US 2019/0128381 A1, is pertinent in this regard. The contents ofthat patent application disclosing the design specifics of that FC gearhousing and cover, and the FC gear design and retention means therein,particularly the description found at 91910041-0048 and shown in FIGS.2A and 2B of that patent application, are incorporated by reference asif fully set forth herein.

Each of the side access port and separate housing can also be positionedon the bottom side of gearbox housing 18, or on the top side of gearboxhousing 18, or at any other location about the perimeter of gearboxhousing 18 from which first and second FC gears 743 and 744 arereasonably accessible, consistent with the orientation of rear plane822. In appropriate design circumstances, First and second FC gears 743and 744 can also be located within a housing having a removable coverattached on rear end 182 itself, such as where FC gear shafts 745 and746 are transversely oriented to rear plane 822 at an acute angle.

As a particular example of the benefits of the fourth embodiment of thesubject invention, a different rotational speed/torque relationship maybe desired when using inline gearbox 1 for a race track applicationinstead of an off-road application. In such a case, first and second FCgears 743 and 744 can be swapped out for gears of different diameters,which changes the rotational speed of output shaft 13 for a givenrotational speed of input shaft 6. In general, the gearbox inputshaft/output shaft speed ratio can be changed by utilizing first andsecond FC gears 743 and 744 of varying diameters without changing any ofthe gears of primary gear train 2.

In the case where it is desirable for the input shaft 6 and output shaft13 to rotate in different directions, an idler gear (not shown) can beinterposed in any of FC gear assemblies 71, 72, 73 and 74, in which casethe first and second FC gears mesh through the idler gear, rather thandirectly. The utilization of such an idler gear is described inconnection with the FC gear housing design and associated componentsdisclosed in U.S. patent application Ser. No. 16/168,957, filed Oct. 24,2018 and published May 2, 2019 as U.S. Patent Publication No. US2019/0128381 A1, which has been incorporated by reference above as iffully set forth herein.

The foregoing detailed description is for illustration only and is notto be deemed as limiting the inventions, which are defined in theappended claims.

1-4. (canceled)
 5. An inline gearbox for a land vehicle that includes anengine having a clutch housing for the transmission of rotational forcefrom the engine to one or more wheels for propelling the land vehicle,the inline gearbox comprising: a gearbox housing having a front end, aside and a rear end, the front end adapted to be joined to the clutchhousing; an input shaft having an axis and contained at least in partwithin the gearbox housing proximate to the front end of the gearboxhousing, the input shaft adapted to receive rotational force from theengine through the clutch housing; a primary gear train contained withinthe gearbox housing comprising (a) a lay shaft having an axis generallyparallel to the axis of the input shaft and rotationally coupled to theinput shaft to receive rotational force from the input shaft, the axesof the input shaft and the lay shaft being spaced-apart to define aforward plane; (b) a drive shaft; and (c) a plurality of selectivelyengaged meshed gear pairs respectively mounted on the lay shaft and thedrive shaft for transmitting rotational force from the lay shaft to thedrive shaft; an output shaft having an axis generally parallel to theaxis of the lay shaft and contained at least in part within the gearboxhousing proximate to the rear end of the gearbox housing, the outputshaft rotationally coupled to the drive shaft to receive rotationalforce from the drive shaft and for transmitting rotational force to theone or more wheels, the axes of the output shaft and the lay shaft beingspaced-apart to define a rear plane; a fast-change gear assemblypositioned proximate the front end of the gearbox housing to one side ofthe forward plane and interposed between the input shaft and the layshaft, the fast-change gear assembly comprising a first fast-change gearand a second fast-change gear meshing with the first fast-change gear,the first fast-change gear and the second fast-change gear havingrespective first and second fast-change gear axes that are bothapproximately perpendicularly oriented to a direction on the forwardplane approximately perpendicular to the axis of the input shaft; thefirst fast-change gear being rotationally coupled to the input shaft soas to rotate with the rotation of the input shaft, and the firstfast-change gear being removable; and the second fast-change gear beingrotationally coupled to the lay shaft so as to rotate the lay shaft uponrotation of the second fast-change gear, and the second fast-change gearbeing removable.
 6. The inline gearbox as in claim 5, further comprisingmeans proximate the front end of the gearbox housing for providingaccess to the fast-change gear assembly for removal thereof withoutseparating the gearbox housing from the clutch housing and withoutdisassembling the primary gear train.
 7. The inline gearbox as in claim6, wherein the first fast-change gear and the second fast-change gear ofthe fast-change gear assembly are contained in an ancillary housingmounted on the exterior of the gearbox housing proximate the front endof the gearbox housing, and a removable cover plate overlays the firstfast-change gear and the second fast-change gear to permit theirremoval.
 8. The inline gearbox as in claim 6, wherein the first andsecond fast-change gear axes are both transversely oriented to adirection on the forward plane approximately parallel to the axis of theinput shaft.
 9. The inline gear box as in claim 8, wherein the first andsecond fast-change gear axes are both transversely oriented to adirection on the forward plane approximately parallel to the axis of theinput shaft at a shaft angle α in the range about 75°≥α≥35°.
 10. Theinline gear box as in claim 9, wherein the shaft angle α is in the rangeof about 60°≥α≥45°.
 11. The inline gearbox as in claim 6, wherein thefirst and second fast-change gear axes are both perpendicularly orientedto a direction on the forward plane approximately parallel to the axisof the input shaft. 12-22. (canceled)